Photoionization detectors (PIDs) employ a lamp to emit photons that ionize gases in the proximity of detector electrodes. An electric field is established between the plates of the electrodes by an applied voltage bias. The electric field induces ionized particles to move to one or another plate, thereby establishing an electric current between the electrodes. The electric current can be processed to extract indication of the presence of gas. For example, PIDs may be used to detect the presence and/or concentration of volatile organic compounds (VOCs) which can pose a threat to human beings.